The invention relates to edible thermoplastics. More particularly to a pet chew made from an edible, protein-based nutritious thermoplastic and methods of use thereof.
For many people, dogs and other pets animals play an important role in providing companionship and safety in the family environment. People are becoming more concerned about the health and hygiene of pets. Pet chews are commonly used to help massage the gums and to strengthen and clean the teeth of the dog or pet.
Most pets are playful in nature which endures the pet to the pet owner. However this playful disposition may be manifest in a destructive manner. Pets may destroy shoes, furniture, curtains, and other objects while expressing their playfulness. As a pet expends its playful energy on a pet chew, the pet is less inclined to destructively chew on household objects.
Chewing plays an important role in a dog""s life. Not only does chewing aid the animal in digesting food and absorbing nutrition, but chewing also promotes healthy, strong teeth. Pets often chew on objects during teething. Puppies between the age of 2 and 6 months chew to relieve the pain of teething. Other young dogs also chew for teething reasons. Even though their teeth are in, the roots are not fully set and chewing relieves the pain of root setting.
For older dogs and other pets, chewing may also be a type of animal play. Most pets enjoy games of catch and will often chew on the object thrown to them.
For about as long as dogs have been a part of people""s life, they have been given animal bones to chew on. The bones relieve the pain of teething, provides an play object, and provides some nutrition to the pet. However, some animal bones can splinter and cause internal injury to the pet.
Accordingly, many chews have been developed for use by pets. However, many chews are made with ingredients that can be harmful to a pet. For example, rawhide bones or floss toys, are enjoyed by most dogs because they contain a natural flavor. However, these chews may splinter and cause internal damage to the pet. Chews made of rawhide may be quickly destroyed by the chewing action of the pet. Furthermore, these artificial chews are inedible and provide little nutrition.
Other artificial chews are made of hard plastic in the form of a bone. These chews are made primarily for larger pets. Smaller pets and puppies cannot chew these plastic bones because of the bones"" size and hardness. The plastic bones are also subject to splintering and care must be taken to prevent internal damage to the pet. Like rawhide bones, the plastic chew are also inedible and provide no nutrition to the pet.
There are several artificial pet chews currently marketed. One example is made of molded synthetic thermoplastic having animal meal dispersed in the plastic polymer. This chew is strong and causes little tooth wear which may occur with natural bones. However this chew is not edible and provides no nutrition. Furthermore, the synthetic polymer is not biodegradable, and can potentially harm the environment.
Other pet chews have been made from corn starch-based material with inter material or a corn starch vinyl-copolymer. These chews lack nutritional value and do not replace or supplement the pet""s regular diet.
In all cases, care must be exercised when the dog is an aggressive chewer and is capable of breaking off an unusually large piece of the artificial chew.
Recently pet chews have been developed that serve different needs. For example environmentally friendly chews have been made of natural corn, wheat, or rice starch with a biodegradable co-polymer. Other chews contain cellulose fiber which is also biodegradable. In order to lessen the risk of injury to a pet, chews have been developed that are resistant to splintering.
However, there remains a need for a pet chew which is completely edible and biodegradable. It would be a further advancement in the art to provide a chew that is safe for pets of all ages and sizes. It would be an additional advancement to provide a pet chew that provided nutritional benefit to the pet. It would be a further advancement in the art if the chew provided complete balanced nutrition to the pet. It would be an additional advancement if the chew aided in maintaining good oral hygiene and the health of the pet""s teeth and gums. It would be a further advancement in the art to provide a pet chew that may be used in training a pet. Such a pet chew and methods of use and manufacture are disclosed and claimed herein.
The present invention is directed to an edible thermoplastic for use in animal chews and pet foods. The thermoplastic is made from a combination of plant and animal derived proteins. Other ingredients are added to ensure that the animal is provided a full compliment of calories and nutrition. To this end, the edible thermoplastic contains starch, fiber, and a metallic salt hydrate. In one preferred embodiment of the invention, the thermoplastic is made from about 30 to 50 wt. % of a mixture of plant protein and animal protein, about 20 to 50 wt. % starch, about 10 to 20 wt. % water, about 1 to 10 wt. % edible fiber, and about 0.5 to 3 wt. % metallic salt hydrate. When the thermoplastic is molded it preferably has a density of about 1.2 to 1.5 g/cubic centimeters.
A currently preferred plant protein is soybean protein. The soybean protein may be obtained from a variety of sources including soy protein concentrate, soy protein isolate, and a combination thereof.
The plant protein may also contain proteins from other plants including grains. Such grains may include, but are not limited to, wheat, rye, oats, barley, corn, rice, millet, and sorghum. The grain proteins are preferably selected from gliadin, gluten, secalin, avenin, hordein, zien, oryzenin, kafirin, and a combination thereof It should be appreciated that a combination of soy, grain, and other plant proteins is within the scope of the present invention.
The animal protein may also come from a variety of sources including, but not limited to, casein, albumin, collagen, gelatin, keratin, and combinations of these and other animal derived proteins.
The starch used in the thermoplastic may be a native, unmodified starch, a chemically altered starch, a pregelatinized starch, and a combination of these and other starches. If a native starch is used, the native starch preferably includes corn starch, high amylose corn starch, potato starch, sweet potato starch, wheat starch, rice starch, tapioca starch, sorghum starch, and a combination of these and other native, unmodified starches.
Examples of chemically altered starches that may be used in the present invention include, but are not limited to, hydroxyethyl starch, hydroxypropyl starch, carboxymethyl starch, acetylated high amylose starch, starch acetate, starch maleate, starch octenylsuccinate, starch succinate, starch phthalate, hydroxypropylate high amylose starch, cross-linked starch, starch phosphates, hydroxy propyl distarch phosphate, starch propionamide, and combinations of these and other chemically altered starches.
The edible fiber of the present invention may include soluble and insoluble fibers. These fibers may include dietary fiber, natural cellulose fiber, and combinations of these and other fibers.
The edible thermoplastic of the present invention preferably includes a metallic salt hydrate. In certain embodiments the metallic salt hydrate may be a calcium, sodium, potassium, zinc, iron, aluminum, or phosphorus salt, or a mixture thereof The metallic salt hydrate may also be a chloride, carbonate, sulfate, lactate, oxalate, borate, phosphate, or acetate salt, or a mixture thereof Examples of some currently preferred metallic salt hydrates that can be used in the present invention include CaCl2.2H2O, CaSO4.2H2O, AlK(SO4)2.12H2O, AlNH4(SO4)2.12H2O, FeCl2.6H2O, CaHPO4.2H2O, Ca(C3H5O3)2.5H2O, and Na2B4O7.10H2O.
In certain embodiments the edible thermoplastic of the present invention may contain flavorings in order to be more palatable to a pet. The flavoring is preferably present be present in an amount ranging from about 0.5 to 15 wt. %. These flavorings may include such natural flavorings as chicken powder, turkey powder, onion powder, garlic powder, plant oils, meat, animal products, chicken meat, chicken fat, beef hide, beef meat, beef fat, pork skin, pork meat, pork fat, dried meat floss, and a combination of these and other flavorings.
The edible thermoplastic may also contain up to 20 wt. % of edible plasticizers. More preferably, the edible thermoplastic may contain 12 to 18 wt. % edible plasticizers. The edible plasticizers preferably include, but are not limited to, glycerol, sorbitan, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, mannitol, sorbitol, and a combination of these and other edible plasticizers.
Up to 10 wt. % of a modifier may be added to improve the mechanical and processing properties of the edible thermoplastic. Such modifiers include sodium alginate, pectin, carrageenan, carob gum, agar, mannan, carbohydrate gum, and combinations thereof.
Nutrients may be added to the thermoplastic to enhance the nutritional content of the edible thermoplastic. Such nutrients may include vitamins, minerals, trace elements, animal fat, plant oil, lecithin, and herbs. The nutrients are preferably added in an amount up to 5 wt. % of the edible thermoplastic.
The vitamins may include, but are not limited to, vitamin A, vitamin, B, vitamin B2, vitamin B3, vitamin B12, vitamin C, vitamin D, vitamin E, niacin, biotin, menadione, folic acid, pyridoxine, and combinations thereof.
Minerals such as calcium, potassium, magnesium, and sodium may also be provided as nutrients. Other nutrients may be contained in trace concentrations such as iron, phosphorus, zinc, manganese, iodine, selenium, and cobalt.
Oils are important in a pet""s diet to provide for a healthy coat of fur. Accordingly, oils such as flax seed oil, sunflower oil, linolenic acid, beef fat, pork fat, and chicken fat may be added to the edible thermoplastic.
Some natural herbs such as flax seed, rosemary, anise, chamomile, valerian, nettle leaf, raspberry leaf, hyssop, yucca, and sage may also be added to provide nutritional benefits to the pet.
Because the thermoplastic is edible and contains nutrients, it is subject to spoilage. Thus, in certain embodiments the thermoplastic may contain preservatives such as calcium propionate, sorbic acid, potassium sorbate, butylated hydroxy anisole (BHA), butylate hydroxy toluene (BHT), ethoxyquin, lactic acid, benzoic acid, sodium benzoate, ethyl-p-hydroxybenzoate, propyl-p-hydroxybenzoate, and combinations of these and other known preservatives.
Pet oral hygiene is important to many pet owners who enjoy a close relationship with the pet. In certain embodiments the thermoplastic contains a hygiene additive to clean and care for the pet""s mouth. Typical hygiene additives may include an anti-tartar agent, calcium pyrophosphate, sodium tripolyphosphate, zinc citrate, calcium hydrogen phosphate, dementholized peppermint oil, spearmint oil, sorbitol, and sorbitan.
The edible thermoplastic has certain physical properties when molded. In one embodiment the molded thermoplastic has a tensile strength from about 1 to 5 MPa.
More preferably, the tensile strength is from about 1.5 to 2.5 MPa. The molded thermoplastic may also have a percentage elongation from about 6 to 100%. More preferably, the percentage elongation is from about 20 to 80%. The molded thermoplastic may also have a Young""s Modulus of about 65 to 2600 MPa. More preferably the Young""s Modulus is about 65 to 1000 MPa.
The invention also relates to an nutritious pet chew molded into a segmented configuration such that individual segments can be broken off and given to the pet as desired. A pet chew may be formed having a plurality of segments separated by a plurality of notches, groves, perforations, or incisions or other localized structural weakenings, hereinafter referred to as scores. The scores serve to weaken the pet chew at predetermined locations. The weakened pet chew can be broken at the score location to remove a segment to give to the pet. The pet chew may be formed in a variety of cross sectional configurations. Such cross sections may include, but are not limited to, a circle, a square, a rectangle, a polygon, an oval, a star, or a fantasy shape such as the outline of a state, a dog breed, or other symbol.
In certain preferred embodiments the pet chew may be formed from the above described thermoplastic, but other known and novel compositions may be used to form the unique segmented configuration within the scope of the present invention.
The pet chew may be formed to be substantially linear or may be curved, circular, or take on any shape.
The pet chew preferably has a convenient length ranging from about 4 to 12 inches. Although the length can extend up to several feet if desired.
The present invention also discloses a method of training pet by using the segmented nutritious pet chew. This method includes obtaining a nutritious pet chew, applying a force to break the pet chew, delivering a segment of the pet chew to a pet, and allowing the pet to chew on the segment.